This application is a U.S. national stage application under 35 U.S.C. § 371 of International Application No. PCT/US13/39790, filed May 6, 2013, claiming priority to U.S. Provisional Patent Application No. 61/771,695, filed Mar. 1, 2013, U.S. Provisional Patent Application No. 61/711,085, filed Oct. 8, 2012, and U.S. Provisional Patent Application No. 61/643,290, filed May 6, 2012. Each of the previously mentioned applications and patents are incorporated by reference in its entirety into this application.
The present invention relates to apparatuses and methods for brewing beverages. More particularly, the invention relates to apparatuses and methods for brewing beverages, such as those from loose coffee or tea.
Drip-style coffee brewers are available in a wide range of different configurations and sizes for use in residential or commercial environments to produce brewed coffee. Such coffee brewers commonly include a water reservoir from which a predetermined volume of water is heated and then dispensed downwardly by dripping onto loose coffee grounds contained within an underlying, upwardly open brew basket. The hot water intermixes with the coffee grounds to produce the desired brewed coffee beverage which is drained from the brew basket through a filter element into an underlying coffee pot such as a carafe or decanter. In one common form, the brewer includes a refillable water reservoir from which the water is delivered through a heating element for drip-flow dispensing into the brew basket. In large respect, the brewing process that involves the intermixing of the coffee grounds with the hot water is concealed within an opaque brewer head. In fact, the brewed coffee is oftentimes not visible until dispensed out into the coffee pot.
An optimal water temperature for extracting flavor from coffee grounds for drip-style coffee brewers can be between 195° and 205° Fahrenheit (“F”). Although, many inexpensive drip-style coffee brewers are incapable of achieving such water temperatures. This is because drip-style coffee brewers are often designed to be relatively inexpensive to manufacture. One way to keep the costs of drip-style coffee brewers low is to use relatively inexpensive heating elements and lower cost operating components. While drip-style coffee brewers are available with better performing heating elements and more expensive components, such brewers are typically more expensive. Thus, while inexpensive heaters can keep of the cost of the drip-style coffee brewers relatively inexpensive, the resultant beverage may not achieve optimal water temperatures.
A variety of modified coffee brewers and related brewing processes have been provided in an attempt to enhance the coffee brewing process, including Applicant's own U.S. Pat. Nos. 6,968,775, 7,240,611 and 7,340,991, the contents of each patent being herein incorporated by reference in their entirety. These patents disclose an improved coffee brewer and method for producing brewed coffee with improved flavor. The coffee brewer includes a brew basket having jet ports connected to a source of heated water and positioned to deliver hot water streams into the brew basket at a location beneath the level of coffee grounds contained therein. These hot water streams turbulently agitate and stir the coffee grounds in the brew basket to produce a substantially fluidized bed of water-borne coffee grounds to improve flavor extraction and enhance aroma. This fluidized bed is directed against one or more mesh filter elements forming a wall portion of the brew basket for outward passage of the thus-brewed coffee which is then directed into an underlying coffee put, such as the aforementioned carafe or the like.
In particular, U.S. Pat. No. 7,340,991 (“the '991 patent”) further discloses a coffee brewer that includes a brew basket having a frontal side wall that incorporates a substantially transparent window visible from the exterior of the coffee brewer. During a brewing cycle, the spinning fluidized bed of water-borne coffee grounds within the brew basket is thus externally observable. In this respect, a light is provided therein in close proximity to the transparent window, for illuminating the visible brewing process. This light (i.e., an LED or the like) is mounted onto the brewer for slide-fit reception into an upstanding pocket or recess formed in the brew basket generally at a lower margin of the basket window, when the brew basket is mounted onto the brewer. The light bulb extends up into this pocket and is positioned in spaced relation from an inboard side of the basket window, thereby defining a chamber between the light and window through which a portion of the water-borne coffee grounds may circulate during a brew cycle. The light back-illuminates the brewing coffee travelling through this chamber by turning on at the initiation of the brew process, and then turns off at the conclusion thereof.
The brewer shown and described in the '991 patent also includes other deficiencies not addressed by the prior art due to the uniqueness of the brewing process disclosed therein. In particular, brewing temperatures achieved with conventional heating elements were not high enough to properly extract the coffee flavors form the coffee grounds. Furthermore, the brew basket chamber is not sealed, which may facilitate additional heat loss from the brew basket during the brew process. Moreover, increasing the wattage of the standard hot water heater caused a tendency to trip a bimetal safety switch, thereby turning off the heater, which can significantly slow down the brewing process, especially the time it takes to evacuate the remaining brewed beverage in the brew basket at the end of the brew cycle. Increased wattage also reduces hydraulic pumping efficiency by converting a higher percentage of water to steam. Additionally, the front of the brewer in and around the arcuate cutout that permits visual observation of the brewing process can warp during the molding process because the arcuate cutout diminishes the hoop strength inherent in the manufacturing process. The brewer and related process disclosed herein address these issues with earlier brewer designs.
Additionally, the lighting system shown and described in the '991 patent has a number of competing drawbacks. Importantly, the overall luminescence of the light must be capable of illuminating the coffee during the brew cycle. Coffee comes in a variety of thicknesses and certain types of “dark” coffee have a level of opacity that prevents or diminishes illumination therein by standardized lighting elements of the size and shape configured to protrude upwardly for slide fit reception into the corresponding pocket in the brew basket. Insufficient luminescence in this respect defeats the purpose of incorporating a lighting element for purposes of observing the intermixture of the water-borne coffee grounds during the brew cycle. Moreover, upward extension of the bulb into the brew basket recess allows the heated water-borne coffee to flow in and around the recess, to transfer heat to the bulb. On one hand this is preferred from the sense that the light provides direct back-illumination, but the drawback is that the bulb can be exposed to temperatures upwards of 100° Celsius during each brew cycle. Such exposure to heat, even for a few minutes, can adversely affect the operational lifespan and efficiency of the lighting element, and especially LEDs.
In fact, it has been realized that the lighting system disclosed in the '991 patent is particularly ineffective at providing adequate back-illumination of especially dark roasts. That is, the thickness of the brewing coffee occludes transmission of light through the transparent window in the brew basket, despite the presence of the chamber between the upstanding pocket and window. While LEDs are available in a wide variety of sizes and shapes, the “standard” sized LED, having a round cross-section of approximately 3 to 5 mm in diameter, is incapable of providing sufficient back-illumination for an observer to watch the brewing process. These standard-sized LEDs are ideal for the size and shape desired to slidably fit into the upstanding pocket, but the drawback is that these LEDs are only cooled by copper wires extending out from the LED housing. Increasing luminescence of this LED requires increasing the current, which naturally results in increased heat and higher operating temperatures. Increasing heat in this respect shortens the lifespan of the LED and increases the risk of premature burnout. The size and shape of the upstanding pocket further prohibits incorporation of a heat sink or the like to function to dissipate heat. In this respect, LED operational lifetime falls sharply with rising current as increased heat across the P-N junction and exposure to heated water-borne coffee during the brewing process increases the risk of premature failure. As a result, and without more, it is not possible to increase the luminescence of such a standard-size LED to adequately illuminate “dark” coffee during the brew cycle.
Accordingly, there exists a significant need in the art for improvements in and to conventional coffee brewers, and specifically the types of coffee brewers generally disclosed in the '991 patent and its progeny, including a need for providing an improved brew basket ventilation system, an overflow avoidance system, methods and systems for efficiently and timely evacuating brewed coffee in the brew basket after the water reservoir is substantially or completely empty, methods and systems for regulating steam and water brewing cycles using a phase control valve, solenoid or mechanical check valve, monitoring and measuring in real-time the water level in the reservoir and activating a down cycle after a threshold low or no water level is identified by a mechanical or electrical sensor, integration of a real-time voltage sensor and related control circuit that regulate the duty cycle the heating element to prevent inadvertent or premature shutoff conditions, and improvements in the related lighting system, namely for achieving significantly enhanced and fuller illumination of the intermixing of heated water and coffee grounds during a brew cycle, without adversely impacting the lifetime operation of the LED or other comparable lighting light source. The present invention fulfills these needs and provides further related advantages.